Calipers



(No Model.)

J. H. OULVER.

OALIPERS.

N0. 371,489. Patented Oct. 11, 1887.

UNITED STATES PATENT @rrrcn.

JAMES H. OULVER, OF SAN FRANCISCO, CALIFORNIA.

CALIPERS.

SPECIFICATION forming part of Letters Patent No. 371,489, dated October11, 1887.

Application filed March 9, 1887. Serial No. 230,299. (No model.)

' 0 aZZ whom it may concern:

Be it known that I, J AMES HENRY CULVER, of the city and county of SanFrancisco, State of California, have invented an Improvement inCalipers; and I hereby declare the following to be a full, clear, andexact description of the same.

My invention relates to certain improve ments in calipers for takinginterior and exterior dimensions.

It consists of a jointed leg upon one side. which allows the leg to beopened or closed independently of the ordinary fulcrum-joint, a stop andholding screw by which it may be returned to exactly the same point andlooked, as will be more fully described by reference to the accompanyingdrawings, in which Figure l is a View showing exterior measurement. Fig.2 is a view showing the application to interior measurement. Fig. 3 is aview from the opposite side, showing the hinged leg turned back. Fig. 4is ascction showing the holding screw and nut.

In a former patent, issued to me April 30, 1867, I show the calipershaving one leg movable upon a pivot-joint formed in a portion of theleg; but this device had no means for insuring the return of the leg tothe exact point after being opened to remove it from the object whichwas being measured.

In my present invention A and Bare the legs of a pair of calipers havingthe joints 0, about which they may be opened and closed, and, ifdesired, the are D and set-screw E, for holding the legs at anyparticular point when the size has been ascertained. In order to allowthe point of the calipers to be applied to surfaces which are smallerthan the outer ends or edges, and at the same time to retain the. sizeafter it has been measured, I make a joint at some portion of one of thelegs A and pivot the outer end, so that it may swing about this jointindependently of the main central joint by which the legs are united. Inthe present case I have shown the upper portion of the leg formed so asto have a shoulder, and an extension through which the pivot-pin Fpasses into the outer or swinging portion of the leg. A beveledshoulder, G, is formed by this portion of the upper part of the leg, andthe inner end of the swinging leg is correspondingly beveled, so thatwhen closed the two shoulders come together and thus hold the legexactly in its proper position. A slot, H, is made in the stationaryportion of the leg, and a pin or screw-shank is fixed in the inner endof the swinging por tion of the leg, so as to just enter this slot whenthe leg is closed, so that the shoulders above described meet, and anut, I, upon this screw is turned until it holds the two parts of theleg firmly together.

The operation will then be as follows: If the outside diameterorthickness of an article is to be taken where it is impossible to re movethe calipers without changing their position, the legs are opened aboutthe central joint and applied in the usual manner to obtain the size.The setscrew is then loosened and the swinging leg turned back, so as tore move the calipers, after which the leg is turned back to the properplace, which will be exactly determined by the shoulder and the rear endof the slot, before described. When the set-screw or nut is turned downuntil it holds the parts firmly together, the calipers maybe used in thesame manner. It will be manifest that inside measurements can be takenwith the same facility, the legs of the calipers being crossed so thatthe points project in opposite directions in the usual way. By this0011- struetion I am enabled to take and retain accurately the sizes ofparts which could not otherwise be measured.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. The calipers having one leg jointed, the outer portion pivoted to theinner, so that it may be opened outwardly, and a shoulder against whichit abuts when closed, in combination with a binding-screw by which it islocked when closed, substantially as herein described.

2. The calipers having one leg jointed, the outer portion pivoted to theinner, sothat it may be opened outwardly, a shoulder against which itabuts when closed, an open-ended slot made in one portion, and a fixedpin projectiug from the other so as to enter the slot, in combinationwith a holding or set nut, by which the parts are held together whenclosed, substantially as herein described.

In witness whereof I have hereunto set my hand. I

S. H. NoURsE, H. 0. LEE.

